A. OUTER SHELL OF MUSSEL 



B. VIEW OF MANTLE AFTER REMOVAL OF LEFT VALVE 



Many of the organs named in C are here visible through the semi-transparent mantle. 



C. EXTERNAL VIEW OF ORGANS AFTER REMOVAL OF LEFT HALF OF MANTLE 



FOOT. 2. MANTLE. 7. INHALANT SIPHON. 12. ANTERIOR RETRACTOR MUSCLE. 



OUTER GILL. 8. ANTERIOR ADDUCTOR MUSCLE. 13. POSTERIOR RETRACTOR MUSCLE. 



INNEK GILL. 9. POSTERIOR ADDUCTOR MUSCLE. 14. 14. LESSER RETRACTOR MUSCLES. 



5- LABIAL PALPS. 



6. EXHALANT SIPHON. 



10. PERICARDIUM. 



11. KEBER'S ORGAN. 



15. PROTRACTOR PEDIS MUSCLE. 



16. MOUTH. 



D. GENERAL VIEW OF INTERNAL ORGANS 



1. FOOT. 



2. ANTERIOR ADDUCTOR MUSCLE. 



3. POSTERIOR ADDUCTOR MUSCLE. 



4. PERICARDIUM. 



5. 5. NEPHRIDIUM. 



6. AORTA. 



7. VENTRICLE. 



8. 8. INTESTINES. 9. RECTUM. 



10. ANUS. 



11. MOUTH. 



12. GILLS. 



13. STOMACH. 



14. LIVER. 



15. AURICLE. 



16. 16. GENITAL GLAND. 



17. NERVE COMMISSURE. 



18. CEREBRO-PLEURAL GANGLION. 



19. PEDAL GANGLION. 



20. VISCKKAL GANGLION. 



21. POSTERIOR RETRACTOR MUSCLE. 



22. RENO-PERICARDIAL OPENING. 



23. OPENING OF NEPHRIDIUM. 



24. OPENING OF GENITAL GLAND. 



25. SIPHON. 



E. INTERIOR OF SHELL, SHOWING ATTACHMENTS OF FOLLOWING MUSCLES 



1. ANTERIOR ADDUCTOR. 4. POSTERIOR RETRACTOR. 6 and 7. ANTERIOR AND POSTERIOR LESSER RETRACTORS. 



2. POSTERIOR ADDUCTOR. 5. PALLIAL MUSCLES. 8. PROTRACTOR PEDIS. 



3. ANTERIOR RETRACTOR. 



